A long standing troublesome area in the art has been the build-up of marine growth on waterborne objects, such as ships, boats, buoys, and pilings, particularly in the ocean waters. Every two or three years the Navy schedules dry dock time for its ships so that, along with other repairs, the bottom of the ship can be scraped clean of marine growth. This marine growth accumulates while a ship is in port, and the problem manifests itself when the ship is underway. Marine growth can slow the cruising speed of a ship by 3 to 5 knots, which is tactically undesirable as well as consuming an excess amount of fuel.
The prior art discloses various apparatuses for cleaning the hulls of ships of their marine growth. A patent to Rogers, U.S. Pat. No. 883,423, discloses an array of cleaners which operate on the exterior of the hull while the ship is underway. These cleaners or scrapers are actuated by the movement of the ship through the water to remove the marine growth. A patent to Inglis, U.S. Pat. No. 622,232, utilizes a cleaning arrangement which is held stationary in the water while the ship moves therethrough. A patent to Quimby, U.S. Pat. No. 623,961, discloses a shroud for the hull of a ship so that a poisonous solution can be disseminated between the ship and the shroud for killing any marine growth. A patent to White, British Pat. No. 5514, discloses a cleaning system which is operated by personnel aboard the ship. These patents disclose marine growth cleaning devices which are not entirely satisfactory, because, once the marine growth is established, it is encrusted too hard to clean by such methods. Sometimes the paint on the hull of the ship is removed by such methods, which can't be replaced unless the ship is drydocked, and all of the methods require a significant amount of work.
The hulls of many ships, as well as other waterborne objects, are covered with an antifouling paint. This paint contains a toxin which is leached into the water slowly over a period of time to retard marine growth. Such paint is effective for up to two years, after which the old paint must be cleaned off and a new coat applied. Presently, there are some questions in regard to the wisdom in utilizing such paints since the toxins are obviously released into the ocean. Obviously, such antifouling paints are polluting in nature and are expensive to apply.
Acccordingly, there has been a long standing need for a simpler way of overcoming the problem of marine growth on waterborne objects, in particular ocean going ships and boats. In the history of man, literally billions of dollars have been expended in an attempt to overcome this problem.